A typical example of a BVD Construction repair

Initial Investigation

When concrete cracks, it allows water/moisture and minerals to penetrate to the reinforcement (or when it is too close to surface - known as having insufficient cover). The presence of air and moisture as well as potentional minerals / chemicals starts to corrode the reinforcement.

When steel reinforcement corrodes it can expand in volume by 7 times it's original volume! This increase in volume can cause the reinforcement to "pop", or debond, chunks of the concrete away. Over time this leads to worsening concrete spalling/cancer.

Years of corroding reinforcement as well as run off from vehicles in this car park led to a large area of concrete spalling, below is our repair!

The Repair

The first stage of the repair is to perform a "tap test", this tap test allows an experienced tedchnician to audibly identify the perimeter of the debonded (or "popped") concrete. Which he marks out in a series of straight lines.

The perimeter is then checked by Ben - our Structural Engineer & Director (as is every area of concrete repair that we undertake). 

Once the perimeter has been signed off Ben. The removal of the debonded concrete can commence.

We then break away the concrete locally around the reinforcement and thoroughly clean out the area. A Zinc rich protective coating is applied to the reinforcement (other protective measures could be used also, but in this instance, Zinc was sufficient),

A further tap test is undertaken to confirm that no debonded concrete remains.

The end result

Once a final inspection has been undertaken by our engineer, we are ready to apply our concrete surface primer (in stages, for a repair this large, as cured bonding primer can often act as a de-bonder if applied with poor timing!)

The repair mortar that has been approved by both our, and the cleint's, engineer is then applied in accordance with the TDS and manufaturer's methodology. The clients requested finish is then applied (in this case - brushed) and a curing compund is spray applied to ensure sufficient curing of the repair mortar.

If you have a concrete repair that needs attention before it worsens, becoming dangerous and increasingly costly, contact us today for a robust, long lasting solution!